The close bond between a mother polar bear and her cub is captured in this picture of the pair as they cuddle up for a snooze in their enclosure at Moscow Zoo.

The five-month-old lies across his mother, Simka's chest aver emerging from a cave and was captured by photographer Sergey Gladyshev when he visited the zoo.

The man-made cave is similar to what the animals try and find to live in during the coldest parts of winter in their native Arctic Circle. But Mr Gladyshev said despite the warmer conditions in Russia, the bears are just as wary of humans when they stare at their offspring.

Feeling sleepy? The polar bear cub cuddles up to his mother in an intimate moment at Moscow ZooA second image captures the moment that the cub emerges from their cave, staring warily into the camera's lens.

Speaking about the second image, Mr Gladyshev said: 'Simka is very protective of her cubs. She is always watching me when I take photos of them.

'I really like this picture, it's like Simka is waiting to pounce on me if I get any closer to the cub.

'The light in the cave makes the picture. Her face looks scary but she is actually quite calm.

'She just wants to know her cub is not in any danger. She always makes sure they behave.

'If they start to play very hard and fight with each other she growls for them to stop.'

The cub, which has not yet been named, was born at the zoo at the end of last year and often pose and stretch in amusing ways.

Mr Gladyshevsaid: 'I have seen them do this a few times and the female cub is always looking like she is posing. I wonder if she thinks she is a model.

'Simka is always there though. She is always watching. She is a very loving mother. Maybe because she feels food is always there for them and does not feel threatened.

'I took the shot when I was around 10 metres away. The mother and her three kids were in some really interesting poses in just the half an hour while they were out in the sun.

'I hope I'll see even more interesting poses as the months go on this year and they head towards adulthood.'Simka and the cub's father, Vrangel, look after their three cubs in the safety of the zoo as nearly half of the world's polar bear sub-populations decline.

But they may again be helping their community thrive and expecting further cubs as the courtship and mating season finished at the end of May.